package Torello.Java.Build;

import Torello.Java.FileTransfer;
import Torello.Java.FileNode;
import Torello.Java.StringParse;
import Torello.Java.RTC;

import Torello.Java.ReadOnly.ReadOnlyList;
import Torello.Java.ReadOnly.ReadOnlyArrayList;

import static Torello.Java.C.BGREEN_BKGND;
import static Torello.Java.C.BRED_BKGND;
import static Torello.Java.C.BCYAN;
import static Torello.Java.C.BGREEN;
import static Torello.Java.C.BYELLOW;
import static Torello.Java.C.RESET;

import java.io.File;
import java.io.IOException;

import java.util.Map;
import java.util.TreeMap;

/**
 * The purpose of a Build-Tool is, fundamentally, to make a project possible by doing what a
 * programmer would otherwise need enter manually into a keyboard hundreds of thousands of times
 * himself.  The package {@lnk Torello.Java.Build} provides a CLI Menu that would performs hundreds
 * and hundreds of otherwise <B STYLE='color: red;'><I>extremely trivial tasks</I></B> via a single 
 * UNIX CLI Command.
 * 
 * <BR /><BR />It is likely that no programmer on earth would determine that running the Standard
 * Java Command <B>{@code 'javac'}</B> at a UNIX prompt to be an overly cumbersome or difficult
 * task.  Building and re-building the Data-Files for a particular project requires just that: 
 * compiling some {@code '.java'} files, and then executing their {@code '.class'} Files in order 
 * to obtain their output.  Everything seems quite trivial so far.
 * 
 * <BR /><BR />Things become difficult when a project (for example the Java-HTML Library Tool) has 
 * such Data-File Building {@code '.java'} classes spread out across quite a number of 
 * <B STYLE='color:red;'>{@code ../data-files/}</B> directories, and furthermore each of those
 * directories have multiple Data-Files Classes to both compile and build.  In such cases, whenever
 * the need arises to tweak, debug, update or add to the
 * <B STYLE='color:red;'>{@code ../data-files/}</B> directories, the value of some sort of 
 * scripting tool starts to look like an invaluable tool in the programmer's arsenal.
 * 
 * <BR /><BR />Why?
 * 
 * <BR /><BR />Because typing:
 * 
 * <BR /><BR /><OL CLASS=JDOL>
 * <LI>{@code 'cd <dir-name>'} and</LI>
 * <LI>{@code 'javac -switches <java-files>'} and</LI>
 * <LI>{@code 'java <class-files>'}</LI>
 * </OL>
 * 
 * <BR /><BR >over and over again is a ROYAL PAIN IN THE ASS.
 * 
 * <BR /><BR />That's what this tool does for you.  It enters all {@code '../data-files/'}
 * sub-directories of all Package Source Directories in your project and compiles then.
 * Afterwards, it invokes the <B>{@link DataFileBuilderClass#build(String) build}</B> Method on
 * any {@code '.class'} files which have implemented the <B>{@link DataFileBuilderClass}</B>
 * inteface.
 * 
 * <BR /><BR /><UL CLASS=JDUL>
 * 
 * <LI> Enter all <B STYLE='color:red;'>{@code my/package/dir/data-files/}</B> directories
 *      <BR ><BR />
 *      </LI>
 * 
 * <LI> Wipe / Delete all Java {@code '.class'}-Files present in {@code ../data-files/} and its
 *      sub-directories.
 *      <BR /><BR />
 *      </LI>
 * 
 * <LI> Invoke {@code 'javac'} (Re-Compile) all {@code '.java'}-Files present in the directory and
 *      its sub-directories.
 *      <BR /><BR />
 *      </LI>
 * 
 * <LI> Scan {@code ../data-files/} and its sub directories for any and all {@code '.class'}-Files.
 *      Afterwards, seek and identify if any of them implement the
 *      {@link DataFileBuilderClass} interface.
 *      <BR /><BR />
 *      </LI>
 * 
 * <LI> Invoke the {@link DataFileBuilderClass#build(String)} method on those classes which do 
 *      implement the aforementioned interface.  If the user has properly written them, those 
 *      classes will produce Data-Files which are needed and required for the particular
 *      Java-Package being examined.
 *      <BR /><BR />
 *      </LI>
 * 
 * <LI> That's all folks!  It is that simple... 😊😊😊</LI>
 * </UL>
 * 
 * <BR /><BR /><B CLASS=JDDescLabel>CLI Output Example:</B>
 * 
 * <BR />The following {@code '.html'}-Page demonstrates what the output looks like when running
 * this class against all of the <B STYLE='color: red;'>{@code '../data-files/'}</B> directries
 * which are utilized by this Java-HTML JAR-Library.  This output was generated by this tool on
 * Janaury 6th, 2025.
 * 
 * <BR /><BR /><B><CODE><A HREF='doc-files/Data-File-Builder.Output.html'>
 * Data-File-Builder.Output.html</A></CODE></B>
 */ 
public class BuildDataFiles
{
    private BuildDataFiles() { }

    /**
     * This method should be invoked by any {@code public static void main} method, and pass 
     * <B STYLE='color: red;'><I>BOTH</I></B> the provided {@code 'String[] argv'} parameter to 
     * this method, <B STYLE='color: red;'><I>AND</I></B> the remained of the required parameters
     * needed.
     * 
     * <BR /><BR /><B CLASS=JDDescLabel>Helper Code:</B>
     * 
     * <BR />This method invokes two Package-Private and Internal-Classes for help.  These external
     * classes are listed above, at the top of this class' documentation page, and also here, below:
     * 
     * <BR /><BR /><UL CLASS=JDUL>
     * 
     * <LI> <B><A HREF='hilite-files/CompileDataFilesBuilders.java.html'>
     *      CompileDataFilesBuilders.java</A></B></LI>
     * 
     * <LI> <B><A HREF='hilite-files/RunDataFilesBuilders.java.html'>
     *      RunDataFilesBuilders.java</A></B></LI>
     * 
     * </UL>
     * 
     * <BR /><BR /><B CLASS=JDDescLabel>Example &amp; Output:</B>
     * 
     * <BR />This class &amp; method are, indeed, utilized by the Java-HTML JAR-Library (this tool)
     * to build its own Data-Files.  The links here are also included above.  These links are to
     * Syntax-Hilited Source - <I>and the output it produces</I>- showing how this method &amp;
     * class may be used.  These links are also included, here, directly below:
     * 
     * <BR /><BR /><UL CLASS=JDUL>
     * 
     * <LI> <B><A HREF='hilite-files/DataFiles.java.html'>
     *      Torello.BuildJAR.DataFiles.java</A></B></LI>
     * 
     * <LI> <B><A HREF='doc-files/Data-File-Builder.Output.html'>
     *      Data-File-Builder.Output.html</A></B></LI>
     * 
     * </UL>
     * 
     * @param pkgList This list of {@link BuildPackage} instances ought to be the exact same list 
     * which is passed to the {@link Config} class instance used for running a build with this 
     * package.
     * 
     * @param argv This is the {@code String[] argv} parameter received from a CLI Processor at the
     * Command-Line.
     * 
     * @param additionalCompilerArgs This should be a list
     * 
     * @param JAVAC_BIN This parameter may be null, and if it is, it shall be safely ignored.  This
     * parameter may include a relative or full path to a binary for the {@code 'javac'} program.
     * 
     * <BR /><BR />When this parameter is null, this Data-File Builder-Class will utilize whichever
     * {@code 'javac'} binary is available within the Operating-System's {@code 'PATH'}
     * Environment-Variable.
     * 
     * @throws IOException If any Operating-System I/O Errors throw.
     */
    public static void build(
            final BuildPackage[]        pkgList,
            final String[]              argv,
            final ReadOnlyList<String>  additionalCompilerArgs,
            final String                JAVAC_BIN
        )
        throws IOException
    {
        final ReadOnlyList<BuildPackage> selectedPackages = DataFilesCLI.run(pkgList, argv);

        final PkgTextBar textBarPrinter = new PkgTextBar
            (selectedPackages, "Working Package", BGREEN_BKGND, BCYAN);

        final Map<String, Integer> totals = new TreeMap<>();

        int maxLen = 0;

        for (final BuildPackage bp : selectedPackages)
        {
            textBarPrinter.print(bp);
            clearClassFiles(bp.pkgRootDirectory + "data-files" + File.separator);
            CompileDataFilesBuilders.compile(bp, additionalCompilerArgs, JAVAC_BIN);
            int numExecuted = RunDataFilesBuilders.run(bp);
            totals.put(bp.fullName, numExecuted);
            if (bp.fullName.length() > maxLen) maxLen = bp.fullName.length();
        }

        if (selectedPackages.size() > 1) printTotals(totals, maxLen+2);
    }


    // ********************************************************************************************
    // ********************************************************************************************
    // Utility / Helper Methods
    // ********************************************************************************************
    // ********************************************************************************************


    // Clear Class Files in a Directory
    private static void clearClassFiles(final String dataFilesDirName) throws IOException
    {
        final FileNode fn = FileNode
            .createRoot(dataFilesDirName)
            .loadTree(-1, FileNode.CLASS_FILES, null);

        FileTransfer.deleteFilesRecursive(fn, null, null, System.out);
    }


    // Print up the little Map that the main for-loop keeps - which contains a tally or count
    // on how many DataFileBuilderClass were found in each of the user's '../data-files/'
    // directories.

    private static void printTotals(Map<String, Integer> m, int MAX)
    {
        System.out.println(
            "\n\n" + BRED_BKGND + " Package Totals: " + RESET + "\n\n" +
            "The table below lists how many Java '.class'-Files were found within the " +
            "'../data-files/' sub-directory (and all of its sub-directories) and implemented " +
            "the 'DataFileBuilderClass' interface.  These classes were all invoked using their " +
            "respective 'DataFileBuilderClass.build(String)' methods.\n"
        );

        for (Map.Entry<String, Integer> e : m.entrySet())
        {
            final String k = e.getKey();
            final String s = StringParse.nChars(' ', MAX - k.length());
            System.out.println(k + s + e.getValue());
        }

        System.out.println();
    }
}